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An Enormous Gravity ‘Hum’ Moves Through the Universe
Astronomers have found a background din of exceptionally long-wavelength gravitational waves pervading the cosmos.
At Long Last, Mathematical Proof That Black Holes Are Stable
The solutions to Einstein’s equations that describe a spinning black hole won’t blow up, even when poked or prodded.
Mass and Angular Momentum, Left Ambiguous by Einstein, Get Defined
Surprising as it may sound, 107 years after the introduction of general relativity, the meanings of basic concepts are still being worked out.
Massive Black Holes Shown to Act Like Quantum Particles
Physicists are using quantum math to understand what happens when black holes collide. In a surprise, they’ve shown that a single particle can describe a collision’s entire gravitational wave.
A New Tool for Finding Dark Matter Digs Up Nothing
Physicists are devising clever new ways to exploit the extreme sensitivity of gravitational wave detectors like LIGO. But so far, they’ve seen no signs of exotica.
Gravitational Waves Should Permanently Distort Space-Time
The “gravitational memory effect” predicts that a passing gravitational wave should forever alter the structure of space-time. Physicists have linked the phenomenon to fundamental cosmic symmetries and a potential solution to the black hole information paradox.
Growing Inventory of Black Holes Offers a Radical Probe of the Cosmos
One black hole is nice, but astrophysicists can do a lot more science with 50 of them.
Debate Erupts Over How ‘Forbidden’ Black Holes Grow
Once missing in action, middleweight black holes have finally been detected. Now researchers are trying to figure out how they grow from small ones.